#include <stdio.h>
#include <pthread.h>


static int pc(
    pthread_t *,
    const pthread_attr_t*,
    void* (*)(void *),
    void *) __attribute__ ((weakref("pthread_create")));
int main()
{
    printf("pthread_create: %p\n", pc);
    if(pc){
        printf("This is multi-thread version\n");
    }else{
        printf("This is a single-thread version\n");
    }
}